Unreal Engine MCP Server

![License: MIT](https://opensource.org/licenses/MIT) ![NPM Package](https://www.npmjs.com/package/unreal-engine-mcp-server) ![MCP SDK](https://github.com/modelcontextprotocol/sdk) ![Unreal Engine](https://www.unrealengine.com/) ![MCP Registry](https://registry.modelcontextprotocol.io/) ![Project Board](https://github.com/users/ChiR24/projects/3) ![Discussions](https://github.com/ChiR24/Unreal_mcp/discussions)

A comprehensive Model Context Protocol (MCP) server that enables AI assistants to control Unreal Engine through a native C++ Automation Bridge plugin. Built with TypeScript and C++.

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Features
Getting Started
Configuration
Available Tools
Docker
Documentation
Community
Development
Contributing

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Features

| Category | Capabilities | |----------|-------------| | Asset Management | Browse, import, duplicate, rename, delete assets; create materials | | Actor Control | Spawn, delete, transform, physics, tags, components | | Editor Control | PIE sessions, camera, viewport, screenshots, bookmarks | | Level Management | Load/save levels, streaming, lighting | | Animation & Physics | Animation BPs, state machines, ragdolls, vehicles, constraints | | Visual Effects | Niagara particles, GPU simulations, procedural effects, debug shapes | | Sequencer | Cinematics, timeline control, camera animations, keyframes | | Graph Editing | Blueprint, Niagara, Material, and Behavior Tree graph manipulation | | Audio | Sound cues, audio components, sound mixes, ambient sounds | | System | Console commands, UBT, tests, logs, project settings, CVars |

Architecture

Native C++ Automation — All operations route through the MCP Automation Bridge plugin
Dual Transport — Native HTTP/SSE (no bridge needed) or WebSocket via TypeScript bridge
Dynamic Type Discovery — Runtime introspection for lights, debug shapes, and sequencer tracks
Graceful Degradation — Server starts even without an active Unreal connection
On-Demand Connection — Retries automation handshakes with exponential backoff
Command Safety — Blocks dangerous console commands with pattern-based validation
Capability Token Auth — Optional token-based authentication for both WS and HTTP transports
Asset Caching — 10-second TTL for improved performance
Metrics Rate Limiting — Per-IP rate limiting (60 req/min) on Prometheus endpoint
Centralized Configuration — Unified class aliases and type definitions

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Getting Started

Prerequisites

Unreal Engine 5.0–5.8 (5.8 preview validated)

Choose your transport:

Option A: Native MCP (recommended) — no additional dependencies
Option B: TypeScript Bridge — requires Node.js 18+

Step 1: Install MCP Server (Option B only — skip for Native MCP)

Skip this step if using Option A: Native MCP Transport (Step 4A below).

NPX (Recommended): ``bash npx unreal-engine-mcp-server ``

Clone & Build: ``bash git clone https://github.com/ChiR24/Unreal_mcp.git cd Unreal_mcp npm install npm run build node dist/cli.js ``

Step 2: Install Unreal Plugin

The MCP Automation Bridge plugin is included at Unreal_mcp/plugins/McpAutomationBridge.

From source (requires a project with code target)

Your project must have a code target (.sln or .xcworkspace). Blueprint-only projects cannot compile native plugins — to convert, add any class via Tools > New C++ Class in the editor.

Method 1: Copy Folder ``text Copy: Unreal_mcp/plugins/McpAutomationBridge/ To: YourUnrealProject/Plugins/McpAutomationBridge/ ``

Method 2: External Plugin Directory (no copy needed)

Open Unreal Editor → Edit → Plugins
Click Plugin Directories (bottom-left)
In Additional Plugin Directories, add the path to Unreal_mcp/plugins/
Restart the editor — the plugin will be picked up from the external location

This saves the path in your .uproject file so the plugin stays linked without copying.

The plugin compiles automatically when you open the project — UE detects the .uplugin + Source/ and runs UnrealBuildTool.

Video Guide:

https://github.com/user-attachments/assets/d8b86ebc-4364-48c9-9781-de854bf3ef7d

⚠️ First-Time Project Open: UE may prompt "Would you like to rebuild them now?" — click Yes. If instead you see "Missing Modules — McpAutomationBridge. Engine modules cannot be compiled at runtime. Please build through your IDE." — open your project in Visual Studio (Win) or Xcode (Mac) and build from there. After that, the editor will open normally with the plugin loaded.

Pre-built (works with any project, including Blueprint-only)

Build the plugin once, then distribute the compiled binaries — no IDE or compilation needed on the target machine.

1. Build: ```bash

macOS / Linux

./scripts/package-plugin.sh /path/to/UE_5.6

Windows

scripts\package-plugin.bat C:\Path\To\UE_5.6 ```

This produces a zip like McpAutomationBridge-v0.5.30-UE5.6-Mac.zip.

2. Install: unzip into YourProject/Plugins/ and open the project. That's it — no compilation step.

Note: pre-built binaries are tied to a specific UE version. A build for 5.6 won't work with 5.5, 5.7, or 5.8.

Step 3: Enable Required Plugins

Enable via Edit → Plugins, then restart the editor.

<details> <summary>Core Plugins (Required)</summary>

| Plugin | Required For | |--------|--------------| | MCP Automation Bridge | All automation operations | | Python Editor Script Plugin | Python-backed editor automation helpers | | Editor Scripting Utilities | Asset/Actor subsystem operations | | Niagara | Visual effects and particle systems | | Gameplay Abilities | manage_gas operations | | Smart Objects | AI smart object operations |

</details>

<details> <summary>Optional Plugins (Auto-enabled)</summary>

| Plugin | Required For | |--------|--------------| | Level Sequence Editor | manage_sequence operations | | Control Rig | animation_physics operations | | GeometryScripting | manage_geometry operations | | Behavior Tree Editor | manage_ai Behavior Tree operations | | Niagara Editor | Niagara authoring | | Environment Query Editor | AI/EQS operations | | MetaSound | manage_audio MetaSound authoring | | StateTree | manage_ai State Tree operations | | Enhanced Input | manage_networking input mapping operations | | Chaos Cloth | Cloth simulation | | Interchange | Asset import/export | | Data Validation | Data validation | | PCG | manage_pcg graph authoring and execution when enabled for the build | | Procedural Mesh Component | Procedural geometry | | OnlineSubsystem | Session/networking operations | | OnlineSubsystemUtils | Session/networking operations |

</details>

💡 Optional plugins are auto-enabled by the MCP Automation Bridge plugin when needed. PCG support is compiled for source projects when the project explicitly enables PCG. Versioned release packages for UE 5.2+ include PCG support.

Step 4: Configure MCP Client

Option A: Native MCP Transport (Direct HTTP — no bridge needed)

The plugin includes a built-in MCP Streamable HTTP server. AI clients connect directly to the plugin over HTTP — no TypeScript bridge, no Node.js, no npm.

Enable in Unreal:

Edit > Project Settings > Plugins > MCP Automation Bridge
Check Enable Native MCP
Set port (default: 3000)
Optionally set Native MCP Instructions for project-specific guidance
Restart the editor

Configure your MCP client to use Streamable HTTP transport at: `` http://localhost:3000/mcp ``

Claude Code: ``bash claude mcp add unreal-engine --transport http http://localhost:3000/mcp ``

Or manually in ~/.claude/settings.json or project .mcp.json: ``json { "mcpServers": { "unreal-engine": { "type": "url", "url": "http://localhost:3000/mcp" } } } ``

Cursor (.cursor/mcp.json): ``json { "mcpServers": { "unreal-engine": { "url": "http://localhost:3000/mcp" } } } ``

Verify it works:

Status bar — look for ● MCP :3000 (2) in the bottom-right of the editor. Green dot = server running, number in parens = active sessions. Click it to open settings.
Output Log — filter by LogMcpNativeTransport to see connections, tool calls, and session activity:

  LogMcpNativeTransport: Native MCP server started on http://localhost:3000/mcp
  LogMcpNativeTransport: MCP session initialized: ... (client: claude-code 2.1.92, active sessions: 1)
  LogMcpNativeTransport: tools/call: inspect (RequestId=...)
  LogMcpNativeTransport: tools/call completed: ... (tool=inspect, success=true)

Features:

SSE streaming for real-time progress during long operations
Multiple concurrent sessions (Cursor + Claude Code + others simultaneously)
Dynamic tool management — core tools load by default, enable more via manage_tools
Python execution via execute_python action (inline code or .py files)
Capability token authentication — enable in project settings for network security

Option B: TypeScript Bridge (stdio — classic setup)

Add to your Claude Desktop / Cursor config file:

Using Clone/Build: ``json { "mcpServers": { "unreal-engine": { "command": "node", "args": ["path/to/Unreal_mcp/dist/cli.js"], "env": { "UE_PROJECT_PATH": "C:/Path/To/YourProject", "MCP_AUTOMATION_PORT": "8091" } } } } ``

Using NPX: ``json { "mcpServers": { "unreal-engine": { "command": "npx", "args": ["unreal-engine-mcp-server"], "env": { "UE_PROJECT_PATH": "C:/Path/To/YourProject" } } } } ``

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Configuration

Environment Variables

# Required
UE_PROJECT_PATH="C:/Path/To/YourProject"

# Automation Bridge
MCP_AUTOMATION_HOST=127.0.0.1
MCP_AUTOMATION_PORT=8091

# LAN Access (optional)
# SECURITY: Set to true to allow binding to non-loopback addresses (e.g., 0.0.0.0)
# Only enable if you understand the security implications.
MCP_AUTOMATION_ALLOW_NON_LOOPBACK=false

# Logging
LOG_LEVEL=info  # debug | info | warn | error

# Optional
MCP_CONNECTION_TIMEOUT_MS=5000
MCP_REQUEST_TIMEOUT_MS=120000
ASSET_LIST_TTL_MS=10000

# Optional Prometheus metrics endpoint
# Loopback-only by default. Non-loopback metrics requires both explicit opt-in and a token.
# MCP_METRICS_PORT=9100
# MCP_METRICS_HOST=127.0.0.1
# MCP_METRICS_ALLOW_NON_LOOPBACK=false
# MCP_METRICS_TOKEN=change-me

# Custom content mount points (comma-separated)
# Plugins with CanContainContent register mount points beyond /Game/.
# MCP_ADDITIONAL_PATH_PREFIXES=/ProjectObject/,/ProjectAnimation/

LAN Access Configuration

By default, the automation bridge only binds to loopback addresses (127.0.0.1) for security. To enable access from other machines on your network:

TypeScript (MCP Server): ``env MCP_AUTOMATION_ALLOW_NON_LOOPBACK=true MCP_AUTOMATION_HOST=0.0.0.0 ``

Unreal Engine Plugin:

Go to Edit → Project Settings → Plugins → MCP Automation Bridge
Under Security, enable "Allow Non Loopback"
Under Connection, set "Listen Host" to 0.0.0.0
Restart the editor

⚠️ Security Warning: Enabling LAN access exposes the automation bridge to your local network. Only use on trusted networks with appropriate firewall rules. Enable capability token authentication (Require Capability Token in project settings) to prevent unauthorized access when using LAN mode.

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Available Tools

23 exposed MCP tools in broad all-tools mode. Related actions live directly on their parent tools so clients load less context without losing capabilities.

<details> <summary>Core Tools</summary>

| Tool | Description | |------|-------------| | manage_asset | Assets, Materials, Render Targets, Behavior Trees | | manage_blueprint | Blueprints, SCS components, graph editing, UMG widgets, layout, bindings, animations | | control_actor | Spawn, delete, transform, physics, tags | | control_editor | PIE, Camera, viewport, screenshots | | manage_level | Load/save, streaming, lighting | | system_control | UBT, Tests, Logs, Project Settings, CVars, Python Execution | | inspect | Object Introspection | | manage_tools | Dynamic tool management (enable/disable at runtime) |

</details>

<details> <summary>World Building</summary>

| Tool | Description | |------|-------------| | build_environment | Landscapes, foliage, procedural terrain, lighting, spline roads/rivers/fences | | manage_level_structure | Levels, sublevels, World Partition, streaming, data layers, HLOD, volumes | | manage_geometry | Procedural mesh creation and editing with Geometry Script | | manage_pcg | PCG graph assets, subgraphs, input/sampler/filter/spawner nodes, pin connections, execution, partition grid size, and node settings |

</details>

<details> <summary>Gameplay Systems</summary>

| Tool | Description | |------|-------------| | animation_physics | Animation BPs, skeletons, sockets, physics assets, cloth, vehicles, ragdolls, Control Rig, IK | | manage_effect | Niagara, particles, debug shapes, GPU simulations | | manage_gas | Gameplay Ability System: abilities, effects, attributes | | manage_character | Character creation, movement, advanced locomotion | | manage_combat | Weapons, projectiles, damage, melee combat | | manage_ai | AI controllers, Behavior Trees, EQS, perception, State Trees, Smart Objects, NavMesh/pathfinding | | manage_inventory | Items, equipment, loot tables, crafting | | manage_interaction | Interactables, destructibles, triggers |

</details>

<details> <summary>Utility</summary>

| Tool | Description | |------|-------------| | manage_audio | Audio Assets, Components, Sound Cues, MetaSounds, Attenuation | | manage_sequence | Sequencer, cinematics, bindings, tracks, playback, keyframes | | manage_networking | Replication, RPCs, network prediction, sessions, split-screen, LAN/voice, game framework, input mappings |

</details>

Supported Asset Types

Blueprints • Materials • Textures • Static Meshes • Skeletal Meshes • Levels • Sounds • Particles • Niagara Systems • Behavior Trees

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Docker

docker build -t unreal-mcp .
docker run -it --rm -e UE_PROJECT_PATH=/project unreal-mcp

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Documentation

| Document | Description | |----------|-------------| | Handler Mappings | TypeScript to C++ routing | | Plugin Extension | C++ plugin architecture | | Testing Guide | How to run and write tests | | Roadmap | Development roadmap |

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Development

npm run build       # Build TypeScript
npm run lint        # Run ESLint
npm run test:unit   # Run unit tests
npm run test:all    # Run all tests

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Community

| Resource | Description | |----------|-------------| | Project Roadmap | Track roadmap progress and priorities | | Discussions | Ask questions, share ideas, get help | | Issues | Report bugs and request features |

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Contributing

Contributions welcome! Please:

Include reproduction steps for bugs
Keep PRs focused and small
Follow existing code style

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License

MIT — See LICENSE

Unreal_mcp

Unreal Engine MCP Server

Table of Contents

Features

Architecture

Getting Started

Prerequisites

Step 1: Install MCP Server (Option B only — skip for Native MCP)

Step 2: Install Unreal Plugin

From source (requires a project with code target)

Pre-built (works with any project, including Blueprint-only)

macOS / Linux

Windows

Step 3: Enable Required Plugins

Step 4: Configure MCP Client

Option A: Native MCP Transport (Direct HTTP — no bridge needed)

Option B: TypeScript Bridge (stdio — classic setup)

Configuration

Environment Variables

LAN Access Configuration

Available Tools

Supported Asset Types

Docker

Documentation

Development

Community

Contributing

License

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